Process for dyeing cellulose acetate silk



Patented May 16, 1933 UNITED. STAT WARE ES PATENT OFFICE RICHARDMETZGEB, OF HEIDELBERG, GERMANY, ASSIGNOB, BY MESNE ASSIGNMENTS; TOGENEBA}; ANILINE WORKS, INC., OF NEW YORK, N. Y., A CORPORATION OF DELA-rnocnss FOR DYEING GELLULOSE ACETATE Sm:

No Drawing. Application filed July 7, 1925, Serial No. 42,046,41141 inGermany July 11, 192;.

The present invention has for its object to provide for an improvedprocess for dyeing cellulose acetate silk.

I have found that cellulose acetate silkcan be dyed in a very excellentand improved manner with a great number of insoluble or difiicultlysoluble compounds when dyeing is carried out in the presence of su'lfitecellulose waste liquor.

The compounds dyed with the aid of the aforesaid sulfite cellulose wasteliquor may be coloring matters or colored or anic compounds in general,insoluble or di cultly soluble in water, as well as components ofdyestufi's, such for example as amino compounds which afterwards arediazotized on the fibre and. coupled with suitable components, ornaphthols or similar components which afterwards are to be developedwith diazo compounds. s

For dyeing, the compounds to be brought on the fibre may be first madeinto a concentrated solution or paste, generally of a colloidal nature,or otherwise finely dispersed in a concentrated form by an addition ofsulfite cellulose waste liquor either alone or in association with oneor more of the so-called synthetic tans, such as substances of thenature of phenol- (or cresol-) formaldehyde-sulfuric acid condensationproducts, or phenolsulfonic acid-sulfur condensation products, carbazolsulfonic acids, crude anthracene or other high tar hydrocarbons sulfonicacids,

or sulfonated mineral oils and the like, and

a dye-bath prepared by diluting such concentrated preparation,or thedyebath may be directly prepared with the compounds to be brought on thefibre while adding sulfite cellulose waste liquor either alone or withthe of ordinary temperature. 100 parts of acetate silk are dyed in thebath for one hour at the said temperature, rinsed and dried, handsomegolden yellow shades being obtained.

As examples of coloring matters dilficultly soluble in water which maybe employed for dyeingcellulose acetate silk in the manner hereinbeforedescribed may be mentioned, for instance the condensation product of3-chlor- (i-nitro-l-amino-benzene and formaldehyde (sec U. S. Patent932,266, dated August 22, 1909), 1.4-diamino-anthraquinone, 1.4.5.8-tetra-amino-anthraquinone, 3-aminobenzanthrone, .Bz l-aminobenzanthronecorrespond ing to the formula alpha naphthylamine (diaz)+meta-phenylene-diamine, beta amino-alpha-naphthraqum one,8-nitro-2-amino-naphthalene, -nitro-1.4- diaminoanthraquinone, methylviolet base, alpha naphthylamine (diaz) para-hydroxybcnzoic acid.

WVhat I claim is:

1. The herein described process for the production of tints on acetylcellulose, which comprises treating the acetyl cellulose with acolloidal preparation from an intermixture of insolubleamino-azo-dyestufi's having an affinity for acetyl cellulose with wastesulfite li uor. J

2. The herein described process for the production of tints on acetylcellulose, which addition of a sulfonic a d the comprises treating theacetyl cellulose with character.

The following example will serve to further illustrate my presentinvention which however is not restricted thereto. The parts are byweight.

Example 2 parts of 8-nitro-2-amino naphthalene are Well mixed with partsof concentrated sul fite cellulose waste liquor of between and andpassed into 2000 parts of water a colloidal preparation from aninter'mixture of aminoanthraquinones having an aifinity for acetylcellulose with waste sulfite liquor.

3. The process of producing dyeings on cellulose acetate silk whichcomprises employing a substance suitable for dyeing acetate silkdifficulty soluble in water, the -said substance containing in itsmolecule at least one aromatic nucleus and at least one nitrogen atom'which is fixed to an aromatic nucleus and otherwise connected withatoms of elements selected from the roup consisting of carbon, nitrogenand ydrogen, in conjunction with sulphite cellulose waste liquor.

' 4. The process of producing'dyeings on' cellulose acetate silk whichcomprises n1ploying a substance suitable for dyeing acetate 4 silk,difliculty soluble in watcrselected from the group consisting ofainino-azo-ilyestufi's and ainino-anthraquinones in conjunction withsulpliite cellulose waste liquor.

In testimony whereof I have hereunto set my hand. 1

RICHARD METZGER.

